Tuesday, February 18, 2014, 12:12

A new target boat was sprayed with TaC coating and let dry.
The target boat is NOT wrapped with Ta-heat shield.

Thermocouples have been attached to the target boat in order to monitor the internal temperature of the new target boat design. 

The boat was installed in Evap#2, chamber is currently being pumped down.

 Tuesday, February 18, 2014, 14:20

Chamber was pumped down this morning to 2.9e-6 Torr. HS cooling water valves were opened, no leaks detected.

TGHT was stepped up to 35A, voltage max set at 14V. TBHT currently at 0A.

Waited ~20min, current stabilized, vacuum started to drop, auto-ramp initiated at 0.2A/min and max setpoint to 700A.

Good vacuum: 3.00e-5 Torr; Bad vacuum: 4.00e-5 Torr.

Temperature reading on left: thermocouple touching edge of target boat; temperature reading on right: thermocouple floating in center of target boat.

 Wednesday, February 19, 2014, 09:11

TGHT has been slowly ramping up overnight at a rate of 0.2A/min

IGP1 = 3.9e-7 Torr, TGHT = 260A; stepping ramping rate up to 2.0A/min

 Wednesday, February 19, 2014, 15:25

IGP1 = 9.4e-7 Torr

Thermocouple T2 = 1267.8C

Internal temp measured with Mikron = 1600C

Increasing max setpoint to 720A due to previous not fully sintered new design of target boat.

 Thursday, February 20, 2014, 09:17

Thermocouple T2 = 1254.5C

Internal temp measured with Mikron = 1811C

IGP1 = 2.6e-7 Torr

Reached max setpoint yesterday evening.

Initiating auto-cooling at 2.0A/min.

 Friday, February 21, 2014, 10:47

Vented and opened chamber this morning.

Target boat not fully sintered. [see attached photos]

Close to a full sinter, and will re-sinter next week with endcaps, so will not re-sinter by itself.